#include <stdio.h>

#define IF {if(
#define THEN ){
#define ELSE } else{
#define FI }}

int main(){

    int x = 0, y = 0;

    IF x == 0
    THEN IF y == 0
         THEN  printf("x == 0");
         FI
    ELSE printf("x != 0");
    FI 

    return 0;
}